Slow charging rate - Cars & Trucks

More info needed. Slow charging rate could be a bad battery, or a bad alternator.

have the charge rate checked , should be between 13 and 14 volts

sounds like the battery hasn't enough charge, try to jump start the vehicle , if starts then check the charge rate to see if alternator is working ok should be around 13.5 - 14 volts, if not then check the drive belt for tightness, if thats ok replace battery

It seems that Ford uses the temperature at the IAT sensor (intake air sensor) to decide charging rate, slow charge rate when hot out and faster when cold out.

The generator does not output (not commanded to) until after the engine is running, so just "key on" will not put the grey or blue wire into a voltage state worth checking.

Unfortunately, it doesn't give any more insight. If the cables are good, the 10a fuse is good, you have voltage at the red wire that's equal to battery voltage reading, the ground is good....it just says replace the generator.

The alternator is internally regulated, but it gets it's working orders from the Computer Module based on the voltage and air temperature at the IAT sensor.

Try looking for and changing the IAT sensor. I don't know if that will work...but it's the only solution I found.

It would be best to slow charge the Battery. You do not want to overwork the Alternator and burn it out. Modern alternators are meant to rebuild a moderately discharged battery or supply on demand energy.

For a deeply compromised battery, the Alternator would have to run the current system demand AND recharge the battery.

Please rate my info.

If it will not hold a charge it must have a bad cell-Try to slow charge it (2 amp rate) if it will not fully charge at a slow rate it is done.

Have the alternator checked,it needs to be checked at the battery,with the lights on,and ac on high blower setting,the voltage reading should be 13.65 volts to 14.25 volts,any less,it needs a new alternator,have the battery checked and charged up on a slow charge,about 36 hours,this will give it a full deep charge,a fast charge does nothing,it only gives it a surface charge,and it does not stay.If this was at all helpful,please rate,thank you,the electric system can not run all the features,and the ignition with the alternator not charging correctly.

As long as you use a slow charg device, yes. Rapid charge devices will blow the fuse or at worst can cause a fire.

You are correct on all accounts. A high number means you dying battery is sucking more juice from the Schumacker. A low number means the battery is not as thirsty. That's how I always think of how to read the meter on mine. Slow charge is a better, deeper charge. The quick charge will get you going, but you should maybe follow it up using the normal mode - car alternator and prolonged drive time. I never use quick charge, personally.